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H Repo

Publications and source records attributed to H Repo.

118 records · Page 7Linked to original sources

Impaired neutrophil chemotaxis in Pelger-Huët anomaly.

A family has previously been described in which four members with Pelger-Huët (P-H) anomaly suffered from recurrent attacks of abdominal pain and fever, while one member, whose polymorphonuclear leucocytes (PMNs) were also hyposegmented, was asymptomatic. We studied chemotaxis, chemokinesis and spontaneous locomotion of PMNs in the three surviving symptomatic sisters, in their asymptomatic brother and in two asymptomatic members of another family with P-H anomaly. The spontaneous migration of the PMNs of the three sisters was significantly slower both under agarose and in a membrane filter than that of the PMNs of the asymptomatic patients with P-H anomaly. Chemotactic and chemokinetic locomotion of the PMNs of the symptomatic sisters was also slow. Our results suggests that the impaired chemotaxis was due to a defect in the intrinsic locomotor capacity of PMNs rather than in their deformability or their responsiveness to the chemotactic stimulus.

Adult↗

Use of leucocyte migration under agarose to study spontaneous and directed locomotion of leucocytes.

Three different cell attractants, together with the parallel use of the leucocyte migration agarose test (LMAT) and the leading front modification (LFM) of the Boyden chamber technique, were employed in studying whether the maximal migration of normal human polymorphonuclear leucocytes (PMNs) is higher toward an attractant (chemotaxis) than in the same attractant incorporated in the culture media (chemokinesis). Using LMAT, the maximal migration distance toward zymosan activated serum (ZAS) was found to be significantly longer than that under agarose mixed with ZAS, thus indicating a chemotactic effect exerted by ZAS. When bacterial culture filtrate (BCF) and casein were used as attractants, the corresponding difference was not significant, implying that the stimulatory effect of these substances on cell migration could be explained by increased random locomotion (chemokinesis) alone. In LFM, the migration rate was significantly higher along a casein gradient than without a gradient. Using ZAS, however, only chemokinesis could be demonstrated. BCF was found to attract PMNs into membrane filters only in the presence of human serum albumin. These observations give credence to the view that both LMAT and LFM are applicable to the in vitro assessment of chemotaxis and chemokinesis but the attractant of choice for this is different in each of the two methods.

Caseins↗

Leukocyte migration agarose test for the assessment of human neutrophil chemotaxis. I. Effects of environmental factors on neutrophil migration under agarose.

To apply the leukocyte migration agarose test (LMAT) to the in vitro assessment of human neutrophil chemotaxis, effects of different culture conditions on neutrophil migration under agarose were studied. Presence of either serum or human serum albumin (HSA) in the culture medium was necessary for detectable neutrophil migration. HSA was preferred since heat-stabile chemotactic agents were found to be generated from fresh serum in the presence of agarose. Additional CO2 in the assay milieu could be replaced by decreasing the NaHCO3 concentration of the culture medium. Both the directed and the spontaneous migration rates of neutrophil leukocytes increased when the concentration of agarose was decreased. Area and distance of migration and cumulative cell count of migrated neutrophil leukocytes were suitable for quantitating the neutrophil migration rate.

Adult↗

Leukocyte migration agarose test for the assessment of human neutrophil chemotaxis. II. Variables in the attraction assay.

Optimal conditions for the attraction assay of human neutrophil leukocytes were studied, using the leukocyte migration agarose test (LMAT). Larger migration areas were obtained toward the attractant wells when they were filled with zymosan-activiated serum (ZAS) in advance than when both the attractant and the cells were added simultaneously. Chemotactic indices (CI; the ratio between the migration rate toward attractant and that toward the control substance) decreased when the number of applied neutrophil leukocytes increased, whereas migration differentials (MD; the difference between the migration rate toward attractant and that toward the control substance) were not markedly affected. Both the spontaneous and the directed migration rates, and CI and MD of neutrophil leukocytes obtained from the same donor on different days varied markedly. When tested repeatedly, however, the neutrophil leukocytes of different donors migrated on the average rather equally toward inactivated serum, as they also did toward ZAS, and the variation of the means of CI and MD was insignificant.

Adult↗

Whole blood luminol-enhanced chemiluminescence: statistical analysis of the responses of different subjects.

Whole blood luminol-enhanced chemiluminescence (CL) was studied using N-formyl-methionyl-leucyl-phenylalanine (FMLP) or opsonized zymosan particles as stimuli. The peak and the integral responses of CL were recorded. In the FMLP-induced CL the initial activation (1-minute values) was also studied, because it coincides with the extracellular production of oxy radicals. Correction factors based on neutrophil count and on haemoglobin concentration were found to decrease dispersion and shape the distributions of the CL responses close to normal in a study of 50 healthy adults. One-minute values were significantly lower in women than in men but there were no significant differences for peak or integral values between sexes. Depressed reaction is in accordance with the previous findings that phagocytic oxy radical production is depressed in female plasma. Thus, our results suggest that 1-minute value is a variable more sensitive than peak or integral value of the CL response.

Adult↗

Circulating soluble interleukin-2 receptor level predicts remission in very early reactive arthritis.

OBJECTIVES: To assess the predictive value of serum soluble interleukin-2 receptor (sIL-2R) levels in patients with acute reactive arthritis (ReA). METHODS: The study includes 26 patients with acute ReA who had participated in a prospective population-based cohort study of very early arthritis. The patients had had arthritis of at least one joint with a maximum duration of 3 months. They were assessed by a rheumatologist on presentation and 6 months later. Serum sIL-2R levels on presentation were measured by the Immulite automated immunoassay analyser. Remission at 6 months, defined by the absence of swollen and tender joints, was related to the baseline sIL-2R level using a permutation test with general scores. Bootstrap estimation was used to derive the 95% confidence interval (CI). RESULTS: A total of 17 patients (65%) were in remission at 6 months and nine patients (35%) still had joint symptoms. In patients reaching remission within 6 months, the mean baseline sIL-2R level, 891 U/mL (95% CI: 658 to 1123), was higher than in patients not reaching remission, 501 U/mL (95% CI: 436 to 566), p = 0.022. CONCLUSIONS: A high serum sIL-2R level at baseline is a predictor of remission in patients with acute ReA.

Acute Disease↗

Serum soluble interleukin-2 receptor predicts early remission in patients with recent-onset rheumatoid arthritis treated with a single disease-modifying antirheumatic drug.

OBJECTIVE: To study the value of baseline serum levels of circulating soluble interleukin-2 receptor (sIL-2R) and soluble E-selectin as predictors of early remission in patients with recent-onset rheumatoid arthritis (RA) receiving a single disease-modifying anti-rheumatic drug (DMARD) (SINGLE) or therapy with a combination of DMARDs (COMBI). METHODS: Baseline (n = 157) serum samples originate from the FIN-RACo (FINnish Rheumatoid Arthritis Combination therapy) trial, in which 195 patients with early and clinically active RA were randomly assigned to receive either SINGLE (initially sulfasalazine) with or without prednisolone, or COMBI therapy (sulfasalazine, methotrexate, hydroxychloroquine, and prednisolone). Of the samples, 76 were from SINGLE patients and 81 from COMBI patients. sIL-2R was measured by automated immunoassay analyzer and sE-selectin by enzyme-linked immunosorbent assay. RESULTS: At six months, 7 (9% [95% CI: 4 to 18]) SINGLE and 19 (23% [95% CI: 15 to 34]) COMBI patients were in remission. In multivariate logistic regression analysis, sIL-2R <442 U/ml and COMBI therapy were the only predictors of remission. The area under receiver operating characteristic curve for sIL-2R level was 0.86 (95% CI: 0.62 to 0.95) in SINGLE and 0.57 (95% CI: 0.42 to 0.71) in COMBI (p = 0.006). In SINGLE, the optimal cut offpoint was 442 U/ml, lower levels predicting remission with sensitivity of 83% (95% CI: 73% to 91%) and specificity of 86% (95% CI: 42% to 100%). Likelihood ratio for positive test was 5.9 (95% CI: 1.6 to 32.8). In multivariate logistic regression analysis, sIL-2R <442 U/ml and COMBI therapy were the only predictors of remission. CONCLUSION: Low baseline serum sIL-2R level predicts early remission of patients with active early RA treated with a single DMARD.

Adult↗

Effects of HLA-B27 positive and negative sera on migration of polymorphonuclear leukocytes in vitro.

Sera from both HLA-B27 positive patients with previous yersinia arthritis and healthy HLA-B27 positive subjects have been reported to stimulate chemokinetic migration of polymorphonuclear leukocytes (PMNs) more than sera from subjects who are HLA-B27 negative. To study this further we tested chemotactic and chemokinetic activities of sera of 213 consecutive blood donors (27 positive for HLA-B27, 12.7%) and those of 55 children (mean age 20 months, range 6-137 months, 8 positive for HLA-B27, 14.5%). Migration distances of PMNs both in membrane filter and under agarose were longer, although not in a statistically significant way, in HLA-B27 positive adult sera than in HLA-B27 negative ones. Chemokinetic activity of sera of HLA-B27 positive children was very similar to that of HLA-B27 negative children. These results give credence to the view that PMN migration enhancing capacity of HLA-B27 positive sera described previously is acquired secondarily and is not genetically determined.

Adult↗